In hydrocarbon treatment processes, it is often necessary at some point in the process to contact and then separate two or more liquids from each other based on density differences. One approach is to use Merichem Company's FIBER FILM® contactor technology in combination with a horizontal settling vessel. These fiber-film type separators/contactors are described in U.S. Pat. Nos. 3,758,404; 3,977,829 and 3,992,156, all of which are incorporated herein by reference. The basic design of a fiber-film type contactor/separator comprises a plurality of vertical hanging fibers contained either totally or partially within a vertical shroud. This shroud is configured to maintain the liquids introduced at the top of the shroud within the inside of the shroud and in contact with the hanging fibers as the liquids flow downward. i.e., downward flow that is parallel to the vertical axis of the fibers and shroud. Once the liquids exit the shroud they enter a separation section that is located below the shroud, typically a horizontal settler, where gravity separates the phases, with the lower density liquids forming an upper layer and the higher density liquids forming a lower layer. Each layer can then be selectively removed from the separation section of the apparatus.
Using the above-described known contacting scheme, refiners have treated low density liquid hydrocarbon feeds with higher density aqueous treating liquids, where both liquids are introduced at the top of the hanging fibers as an admixture such that gravity pulls the liquid admixture vertically down the hanging fibers that are contained within the shroud. Although such contacting schemes have found some amount of success, there is room for improvement, specifically with regard to flexible process configuration that lead to cost savings in new plant construction and old equipment modification. The present invention provides such an improvement over traditional standalone down flow contactors that require more piping, level control instruments, control valves, and more plot space to achieve the same functionality, especially in two-stage configurations. These and other improvements of the present invention will become evident from the following description and accompanying drawings